Show cash on delivery (COD) based on applied coupons in WooCommerce - php

Question

I am trying to have cash on delivery (COD) enabled only for customers that use certain type off coupons.
I have an existing code that, when coupons of a certain type are entered, converts the product sales price to the regular product price.
Now I would like to add that cash on delivery (COD) only is available for valid coupons within the same function.
The part that I have tried to add is this:
if ($coupons = WC()->cart->get_applied_coupons() == False )
unset( $available_gateways['cod'] );
Resulting in:
add_action( 'woocommerce_before_calculate_totals', 'add_custom_price', 10, 1);
function add_custom_price( $cart_object) {
global $woocommerce;
if ( is_admin() && ! defined( 'DOING_AJAX' ) )
return;
$coupon = False;
if ($coupons = WC()->cart->get_applied_coupons() == False )
unset( $available_gateways['cod'] );
if ($coupons = WC()->cart->get_applied_coupons() == False )
$coupon = False;
else {
foreach ( WC()->cart->get_applied_coupons() as $code ) {
$coupons1 = new WC_Coupon( $code );
if ($coupons1->type == 'percent_product' || $coupons1->type == 'percent')
$coupon = True;
}
}
if ($coupon == True)
foreach ( $cart_object->get_cart() as $cart_item )
{
$price = $cart_item['data']->regular_price;
$cart_item['data']->set_price( $price );
}
}
This does not give real error messages, but certainly not the desired result either. Any advice?

Answer 1

First of all I have rewritten your existing code, the part that converts sale prices to regular prices when a certain type of coupon is applied. This because your current code contains outdated methods:
function action_woocommerce_before_calculate_totals( $cart ) {
if ( is_admin() && ! defined( 'DOING_AJAX' ) ) return;
if ( did_action( 'woocommerce_before_calculate_totals' ) >= 2 ) return;
// Initialize
$flag = false;
// Applied coupons only
if ( sizeof( $cart->get_applied_coupons() ) >= 1 ) {
// Loop trough
foreach ( $cart->get_applied_coupons() as $coupon_code ) {
// Get an instance of the WC_Coupon Object
$coupon = new WC_Coupon( $coupon_code );
// Only for certain types, several can be added, separated by a comma
if ( in_array( $coupon->get_discount_type(), array( 'percent', 'fixed_product', 'percent_product' ) ) ) {
$flag = true;
break;
}
}
}
// True
if ( $flag ) {
// Loop through cart items
foreach ( $cart->get_cart() as $cart_item ) {
// Get regular price
$regular_price = $cart_item['data']->get_regular_price();
// Set new price
$cart_item['data']->set_price( $regular_price );
}
}
}
add_action( 'woocommerce_before_calculate_totals', 'action_woocommerce_before_calculate_totals', 10, 1 );
Then to only make COD active, if coupons of a certain type are applied you can use the woocommerce_available_payment_gateways hook
By default COD will not be available:
// Payment gateways
function filter_woocommerce_available_payment_gateways( $payment_gateways ) {
// Not on admin
if ( is_admin() ) return $payment_gateways;
// Initialize
$flag = false;
// WC Cart
if ( WC()->cart ) {
// Get cart
$cart = WC()->cart;
// Applied coupons only
if ( sizeof( $cart->get_applied_coupons() ) >= 1 ) {
// Loop trough
foreach ( $cart->get_applied_coupons() as $coupon_code ) {
// Get an instance of the WC_Coupon Object
$coupon = new WC_Coupon( $coupon_code );
// Only for certain types, several can be added, separated by a comma
if ( in_array( $coupon->get_discount_type(), array( 'percent', 'fixed_product', 'percent_product' ) ) ) {
$flag = true;
break;
}
}
}
}
// NOT true, so false
if ( ! $flag ) {
// Cod
if ( isset( $payment_gateways['cod'] ) ) {
unset( $payment_gateways['cod'] );
}
}
return $payment_gateways;
}
add_filter( 'woocommerce_available_payment_gateways', 'filter_woocommerce_available_payment_gateways', 10, 1 );
Both codes go goes in functions.php file of the active child theme (or active theme).
Tested in WordPress 5.8.1 and WooCommerce 5.8.0